Improvement in sewing-machines



4 Sheets-Sheet 1 J. A. BRADSHAW.

Sewing Machine. v

Patgntd 5 28', 1848.

m umunnn N FETEHS. Photvulhngrlphcr. Waihinglnn. 0.8

4 Sheets-Sheet 2. J. A. BRADSHAW.

v Sewing Machine.

No. 5,942. Patented Nov. 28, 1848( N4 PETERS, PMloLithognphar,Wnhingiun. BIC

4 Sheets-Sheet 3.

. BRADSHAW.

ing Machine.

Sew

Patented Nov. 28, 1848.

N. PETERS. Flloln-Lilhngnpher. Washington. D. C.

4 SheetS-Sh9et4. J. A. BRADSHAW.

Sewing Machine! No. 5,942. v Patented Nov. 28, 1848.

UNITE STATES JNO. A. BRADSHAW, or LOWELL, MASSACHUSETTS.

' IMPROVEMENT IN SEWING-MACHINES.

Specification forming part of Letters Patent No. 5,942,

dated November 28, 1848.

i" 0 all whom it may concern:

Be it known that I, JOHN A. BRADSHAW, of the town of Lowell, in thecounty of Middlesex and State of Massachusetts, have invented certainnew and useful Improvements in the Machine for Sewing Seams in Cloth andother Substances; and I do hereby declare that the following is a full,clear, and exact description of the construction and operation of thesame, reference being had to the annexed drawings, making a part of thisspecification, in which Figure 1 is azop or birds-eye view of themachine. Fig. is an elevation of the front or side A, Fig. 1. Fig. 3 isan elevation of the end B, Fig. 1. Fig. 4 is an elevation of the back orside 0, Fig. 1. Fig. 5 is a plan, and Fig. 6 is a section, of thedriver. Fig. 7 is a perspective view of the bobbin-case. Fig. 8 is avertical longitudinal section of the bobbiircase and the helical springand perforated rubber plate, showing the manner in which the thread iswound upon the bobbin and how it passes through between the perforatedrubber and the plug to the outside of the case. Fig. 9 is a section ofthe clamp for holding the cloth, showing the manner of suspending it tothe box. Fig. 10 is a section showing the flying bobbin-case in the actof passing through the loop of the first threadat the moment after theneedle has been drawn back slightly to form the loop. Fig. 11 shows themanner of forming the loop of the seam. Fig. 12 represents the needlepassed through the cloth with the thread to form a stitch.

Similar letters refer to corresponding parts in the several figures.

In the machine for sewing patented by Elias Howe, J r., there exist manydefects, which render its use difficult and its operation 1111- certain,which defects it is the object of my invention to remedy. Some of thesedefects are enumerated and described as follows: The curved needle usedin Howes machine will not by itself form the loop in the thread, whichis necessary for the flying bobbin, with its case, to pass through, andhas, therefore, to be aided in that operation by a lifting-pin, with thenecessary mechanism to operate it. This is a very bungling device, andis a great incum brance to the action of the machine, being'animpediment in the way of introducing the cloth to be sewed, difficult tokeep properly adjusted, and very frequently gets entangled able, and theneedles costly and difficult to replace, it is therefore very importantthat their breaking in this manner be prevented,

which in my machine is done in the most effectual manner by dispensingwith the liftingpin altogether, the loop for the flying bobbin to passthrough being made with certainty and of the proper form by means of myangular needle moved in a particular manner just'before theflying-bobbin case is thrown. The

shuttle and its bobbin for giving off the thread Y 'in Howes machine arevery defective, as will' be quite evident on' an examination of them.The bobbin is of a cylindrical form, and the thread is wound evenly uponit. 1 To be again unwound with facility and uniformity the thread shouldbe pulled in the direction of a tangent to the cylinder, which, from theconstruction of this shuttle andbobbin, it is impossible to do, as thethread passes out through an aperture in the side of the shuttleopposite to the middle of the bobbin. Consequently, when the thread isunwinding from either end of it, the unwinding coil will press obliquelyagainst theadjacent coil toward the aperture,

and thereby create a greatdeal of frictionsometimes sufficient-to breakthe thread, and

always enough to draw the stitches much tighter than when the thread isbeing unwound from the center of the bobbin. This irregularity in thetension of the thread, from the peculiar manner in which the stitchesare made by this machine, operates very finijuriously upon the qualityof the sewing. The badlycontrived shuttle of the Howe machine rendersindispensable the use of the clipping-piece, lever, cam, small lever inthe sliding box, and spring'operating on it. These parts are alldispensed with by the use of my neat and simple bobbin-case, which givesoff its thread with certainty and uniformity and keeps it at anyrequired degree of tension, and

in traversing the sliding box unerringly forms theloop to make thestitch every time the needle passes through the cloth or other substancebeing'sewed. The baster-plate in the Howe machine is very inconvenientand trons This accident blesome to use, because of its extreme limberThe needle 3 (which constitutes one of my ness, which, renders itdifficult to keep it from twisting and letting the cloth slip off, andalso because of the numerous sharp points which unavoidably pierce andscratch the hands of the operator in the most annoying manner. Thesedifficulties are obviated in my machine by the use of the clamphereinafter described, which is a very simple and efficient device,possessing all the advantages and liable to none of the objections ofthe baster-plate above mentioned.

Having now enumerated the most promineut defects in the old machine, Iwill proceed to describe the construction and operation of myimprovements to remedy the same, so that others skilled in the art maybe enabled to make and use them.

The base or platform 0, on which the carriageis placed, and to which theclamp i is attached; the carriage I, with its frame-work to support theoperative portion of the machine; the cam-shaft S, with the cams B K L,&c. the balance-wheel G, the picker-staves I) b, and drivers D", theneedle-arm a, the system of compound straight and bent levers M, &c.,with the click T, ratchct-wl'leel R, cogged pinions R R, and rack H, bythe operation of whichthe carriage is moved simultaneously with theformation of the seam, are all constructed and operated in a mannersubstantially the same as the corresponding parts of the Howe machine.Aparticular description of them is therefore unnecessary, and I shallmerely refer to them in describing my improvements.

0, Figs. 1, 3, and 4, is the base or platform,

having a rack, H, running longitudinally along I its upper surfaceparallel to the guides or ways 0, on which the carriage moves. I is thecarriage upon which the standards QQ are erected, which support thecam-shaft S, with its cam B, which operates the needle arm a. and cams KK, that move the vibrating picker staves or arms I) b, and the cam L,which operates the bent lever M, and with it the system of compoundlevers M M M, con

nected together by j oint-pins, which, by means of a dog, T, turn theratchet-wheel R. and the cog-wheel R, which is secured to theratchetwheel shaft, and which gears into the cogwheel R, which meshesinto the rack H. These wheels, operated by the aforesaid levers and cam,move the carriage along upon the ways 0 every time the needle iswithdrawn from the cloth a distance equal to the length it is requiredto make the next stitch. The cloth, being held between the clamp boards,and these being attached to the way 0', .which is stationary, remains inthe same position ,while the machine carrying the needle and threadmovesalong by the side of the seam as fast as it is formed. The lengthof the stitch is varied by turning the thumb-screw N which brings thelever M more or less within the scope of the action of the cam L, whichmoves it as in the Howe machine.

improvements) is of the form seen at y, Figs. 3, 10, and 12, and isattached to the vibrating lever a, by which, in the format-ion of eachstitch, it is caused to pierce and protrude through the cloth, carryingwith it the bend or loop of the first thread. The needle has two angularbends, as represented. Through the angle nearest the point the eye ismade, through which, from the underside, the thread from the bobbin A ispassed, ,as represented by the line 12, and from thence to the cloth.The needle is made of this shape in order that while it is passingthrough the cloth a loop or 3 space for the bobbin-case to pass throughmay be formed between the thread, which passes in a straight line fromthe eye back to the cloth a, where the stitch is being formed, asrepresented in Fig. 12, the thread forming theloug side or hypotenuse ofan obtuse-angled triangle when extended or stretched by the entrance ofthe needle the full extent that it is designed to enter, said portion ofthe thread being made to bow upward and form a loop for the passage ofthe bobbin-case through the same by the sudden withdrawal of the needlea short distance, said loop being directly in the path of thebobbin-case, as seen in Fig. 1.0, the beak or pointed end of whichentering said loop without obstruction and passing between the needleand' the thread, drawing out the slack of thelatter to form the looplarge enough for the bobbin-case to pass through with facility, whichgives outthesecoud thread that is to be drawn into the cloth by the saidloop .of the first thread 011 the withdrawal of the needle from thecloth, as'seen in Fig. 1.0. Every time the needle pierces the cloth thevibrating clamp h is made to press the cloth firmly against the side ofthe curved trough or segment-box until after the needle is againwithdrawn. This prevents any movement of the cloth during the formationof the stitch. The portion of the needle from the arm a to the firstangle is made straight. From thence it is bent'upward, forming an angleof about one hundred and fifty-four degrees with the first-namedportion. It is then' bent downward at the point, forming an angle ofabout one hundred and sixty-seven degrees with the middle or last-namedportion. This shape of needle, when operated in the'manner abovedescribed, will form the loop in the transverse thread without the useof the lifting pi lrheretofore used in the Howe machine.

The case 0 Figs. 7 and 8, of the flying bobbin is made of some kind ofsuitable metal and of convenient dimensions. The exterior form of thebody of the case is that of a segment of a cylinder larger than ahalfeylind'er, while its interior is cylindrical. Its beak or front endis sen1i-conical in shape and solid, having a tongue, 0 formed on itsunder side corresponding to the groove in the bottom of the guide-troughor segment-box f, in which it runs. The back end of the case is closedup by a solid metallic plug, 0, screwed therein.

Within the case is placed abobbin, B, to hold the second thread withwhich the seam is made. Upon the spindle B" of the bobbin is secured acollar, B near its large end, which collar corresponds in diameter withthe interior of the case. The large end of the spindle which projectsbeyond the collar of the bobbin fits into a hole made in the front endof the case. The thread is wound upon the spindle of the bobbin in theform of a cone, as represented in Fig. 8, the apex of which is placedtoward the rear end of the case, so that it may be easily unwound bybeing drawn in-a line with the spindle. Over the spindle, and fittinginto a groove formed upon the collar thereof, is placed a helicalspring, 8, Fig. 8, which fills the interior of the case C from thecollar B" to the plug Oiin the rear. Into the rear end of this helix around collar, G is inserted, perforatedin the center, with a small holefor the thread or silk'to pass, the diameter of the larger portion bfthe collar corresponding with the diameter of the in side of the case.The thread from the bobbin passes through the hole in the center of thecollar and out between the collar and plug through an aperture in. theside of the case to the exteriorthereof. The collar being pressed uponby the spring acts as afriction-rubber to prevent the thread from beingdrawn from the bobbin without being subjected to a suflicient degree oftension. The pressure of the rubber may be increased by screwing in theplug, which presses the collar harder against the spring, and in thismanner the thread may be drawn with any degree of tension that it willbear. On the exteriorsurface of the case are two longitudinal grooves orchannels, 0 0, connected by a transverse tunnel or tube at CT, throughwhich the thread is caused to pass. These passages for the thread topass through are to aid the spring and friction-rubber in giving it therequired tension, and also for the purpose of diminishing its tendencyto kink. The stitches are formed, as in the Howe machine, by the threadfrom the bobbin-case a" being looped round the thread of the needle anddrawn together with a tension corresponding to the force with which thefrictionrubbers act upon the thread; The manner in which the threads arelooped together in the seam will appear more plainly by reference beinghad to Fig. 1.1, in which the dotted line represents the loops made bythe first thread and the black those made by the second.

' The clamp for holding the cloth is composed of two boards or plates,ii, lined ontheirsides next the article being held with cloth or othersuitable substance, and providedwith dowelpins to keep them in theirproper relative position. The cloth or other article to be sewed isplaced between the said clamp-boards, which are held together firmly bythe springs Z, which may be of. the form represented in the drawings,Fig. 2', or of any form more suit able. This clamp is suspended to theunder side of the segmentbox or guide-troughby means of a flange or lipfastened to the upper edge of the inner clamp-board, which plate ishooked upon a pin inserted into the box or trough, and is prevented frommoving longi tud'inally by a hook, which is attached by one of its endsto the way or clamp-board. The ends of the clamp are at liberty to movevertically for the purpose of sewing. angular and curved seams. The endof the clamp may be suspended to a fixed post or bar by a spring, suchas that represented at m, Fig. 3, or by any suitable means. One

edge of the aforesaid clamp is made straight sewing .variousdescriptions of curved seams, and with what facility pieces of cloth canbe clamped without the use of basting-thread or basting pins or plates,in addition to the ad-' I vantages heretofore enumerated. The flexiend.I It not only allows portions of the cloth to slip from some of thepins, but that which is sustained on the remaining pins will hang downbetween the pins and make the seam crooked; and the pins will pierceholes in the cloth, which will injure it materially; and when satinand-silk 'vests are being sewed, these'holes are very objectionable. TheHowe machine is stationary, and the baster-plate or cloth-holderprogressive. chine is progressive and the cloth-holder stationary.

Having thus fully described the manner in which 1 construct my machinefor sewing seams and shown the operation thereof, what I claim as myinvention, and desire to secure by Letters Patent, is-

1. The combination of the rubber or friction plate, helical spring, andbobbin with the case, as described, for producing degreeof tension inthe thread while being unwound from the bobbin, substantiallyas setforth, whether the several parts be combined and arranged in the mannerdescribed, or other mode substantially the same, bywhich simi- I I larresults are produced.

2. The peculiar bobbincase carrying the second thread, as abovedescribed. 4

JOHNfA. BRADSHAW.

Witnesses:

WILLIAM A. RICHARDSON,

' 'I. P. MARTIN.

track 0, having the other end inserted into an aperture in the The Vhenthis edge is used; the

danger of separating the edges of the cloth in ble baster-plate will notanswer the desired- The, Bradshaw majthe required construction of theflying-

